Tension device and heat exchange fin manufacturing machine

ABSTRACT

The tension device comprises: a feeding unit for feeding a band-shaped metal plate to a press unit; and a holding unit for applying tension to the band-shaped metal plate. The feeding unit is constituted by a moving member and a feeding pin. The front end of the feeding pin has a slope face so as to engage with a collared through-hole of the band-shaped metal plate when the moving member moves in a feeding direction of the band-shaped metal plate and so as to disengage therefrom when the moving member stops and moves in the reverse direction. The holding unit has a holding member, which holds and applies prescribed tension to the band-shaped metal plate when the moving member stops and which releases the band-shaped metal plate when the moving member starts to move in the feeding direction.

BACKGROUND OF THE INVENTION

The present invention relates to a tension device and a heat exchangefin manufacturing machine, more precisely relates to a tension device,which comprises a feeding unit for intermittently feeding a band-shapedmetal plate to a press unit so as to form collared through-holes thereinand a holding unit for applying tension to a part of the band-shapedmetal plate located between the feeding unit and the holding unit whenthe press unit stops feeding the band-shaped metal plate to the pressunit, and a heat exchange fin manufacturing machine having the tensiondevice.

Heat exchange fins for air conditioners, etc. are manufactured by, forexample, a heat exchange fin manufacturing machine shown in FIG. 6. Heatexchange fins are formed by processing a band-shaped metal plate 10,which is composed of, for example, aluminum. The band-shaped metal plate10 is extended from a coil 12. The band-shaped metal plate 10 extendedfrom the coil 12 is inserted into an oil unit 16 so as to applymachining oil to a surface thereof, and then the band-shaped metal plate10 is fed to a press die 20 of a press unit 18.

Collared through-holes, which have collars of a prescribed height, areformed in the band-shaped metal plate 10, by the press die 20, andequally spaced in the longitudinal direction of the band-shaped metalplate 10.

The band-shaped metal plate 10, in which the collared thorough-holeshave been formed, is sent a prescribed distance in a prescribeddirection, and then cut by a cutter 26 so as to form a heat exchange finhaving a prescribed length. The heat exchange fin is accommodated in astacking unit.

In the press unit 18 shown in FIG. 6, a hitch feeder 29 intermittentlyfeeds the band-shaped metal plate 10 including the collaredthrough-holes in a prescribed direction (see, for example, JapanesePatent Gazette No. 2006-21876).

The hitch feeder 29 has driving means shown in FIG. 7. In the drivingmeans, a connection rod 32 is connected to an eccentric pin of a crank30, which synchronously rotates with the press unit 18, and a first link36, which turns about a pin 34, and a second link 42, which is connectedto a lever 40 turning about a shaft 38, are connected to a pin 44provided to a lower end of the connection rod 32. A cylinder unit 37 isprovided to the first link 36 so as to adjust a swing angle thereof. Inthe driving means shown in FIG. 7, by rotating the crank 30, theconnection rod 32 reciprocally turns the lever 40 by the first link 36and the second link 42.

As shown in FIG. 8, a link 46 is connected to an upper end of the liver40 so as to reciprocally move a moving member 50 along a guide 48.

As shown in FIG. 9A, a feeding pin 52, whose front end part has a slopeface, is provided to the moving member 50. The front end part of thefeeding pin 52 is upwardly biased by a spring 56 and projected upwardfrom an upper face of a reference plate, which is provided above themoving member 50, via a slit 54 of the reference plate.

As shown in FIG. 9A, the front end part of the feeding pin 52, which isprojected upward from the upper face of the reference plate, is insertedinto a collared through-hole 11 of the band-shaped metal plate 10, whichhas been mounted on the reference plate.

By moving the moving member 50 in a direction A (see FIG. 9A), theband-shaped metal plate 10 is moved in the direction A.

On the other hand, when the moving member 50 is moved in the reversedirection or a direction B (see FIG. 9B), the slope face of the frontend part of the feeding pin 52 contacts an inner edge of the collaredthrough-hole 11 and is moved in the direction B. With this action, thefeeding pin 52 is retracted into the moving member 50 against a biasingforce of the spring 56, which is applied to the feeding pin 52.Therefore, when the moving member 50 is moved in the direction B,feeding the band-shaped metal plate 10 can be stopped and theband-shaped metal plate 10 can be intermittently fed in the direction A.

In the feeding unit shown in FIGS. 9A and 9B, the moving member can besynchronously moved with the press unit 18, and a feeding speed of theband-shaped metal plate 10 can be easily changed on the basis ofincreasing and reducing a rotational speed of the press unit 18.

However, in the feeding unit shown in FIGS. 9A and 9B, if a rotationalspeed of the press unit 18 is high, the band-shaped metal plate 10 willmove beyond the front end part of the feeding pin 52, which includes theslope face, when the movement of the moving member 50 in the directionof feeding the band-shaped metal plate 10 is stopped. Namely, theband-shaped metal plate 10 will be excessively sent.

If the band-shaped metal plate 10 is excessively sent, the press unit 18processes wrong parts of the band-shaped metal plate 10 so that many badproducts will be produced.

SUMMARY OF THE INVENTION

The present invention was conceived to solve the above describedproblems.

An object of the present invention is to provide a tension device, whichis capable of applying tension to a band-shaped metal plate when afeeding unit stops feeding the band-shaped metal plate so as not toexcessively feed the band-shaped metal plate.

Another object is to provide a heat exchange fin manufacturing machineincluding the tension device of the present invention.

The inventors have studied to solve the problems. Thus, they providedmeans for holding the band-shaped metal plate 10 in the press die 20 ofthe press unit 18 so as to apply tension to the band-shaped metal plate10 when the moving member 50 is stopped.

However, the holding means must hold the band-shaped metal plate 10before perfectly stopping the moving member 50 so as to apply prescribedtension to the band-shaped metal plate 10. On the other hand, in thepress unit 20 which is synchronized with the press unit 18, if theholding member holds the band-shaped metal plate 10 before perfectlystopping the moving member 50, a timing of releasing the band-shapedmetal plate 10 will lag behind starting the moving member 50 to move inthe feeding direction. With this action, a great force is applied to thecollared through-hole, in which the feeding pin 52 has been inserted,and the collared through-hole will be deformed. Therefore, it isdifficult for unskilled operators to adjust the timings of holding andreleasing the band-shaped metal plate 10.

Further, a distance of excessively feeding the band-shaped metal plate10 is varied according to the rotational speed of the press unit 18. Incase of changing the rotational speed of the press unit 18, the timingsof holding and releasing the band-shaped metal plate 10 must bereadjusted.

The inventors have further studied to invent a tension device, which iscapable of easily adjusting the timings of holding and releasing theband-shaped metal plate so as to apply prescribed tension to theband-shaped metal plate even if the rotational speed of the press unitis changed.

As a result, in case that the feeding unit stops feeding the band-shapedmetal plate to the press unit, it is effective to separately provide aholding unit for holding the band-shaped metal plate and applyingprescribed tension thereto from the press unit and adjust the timings ofholding and releasing the band-shaped metal plate according to therotational speed of the press unit. Then, they reached the presentinvention.

To achieve the objects, the present invention has following structures.

Namely, the tension device of the present invention comprises:

a feeding unit for intermittently feeding a band-shaped metal plate to apress unit so as to form collared through-holes therein; and

a holding unit for applying tension to a part of the band-shaped metalplate located between the feeding unit and the holding unit when thepress unit stops feeding the band-shaped metal plate to the press unit,

the feeding unit is constituted by a moving member, which is capable ofreciprocally moving in the longitudinal direction of the band-shapedmetal plate, and a feeding pin, whose front end is biased toward theband-shaped metal plate by a biasing member provided in the movingmember,

the front end of the feeding pin has a slope face so as to insert thefront end of the feeding pin into the collared through-hole of theband-shaped metal plate and engage the same with an inner edge of thecollared through-hole when the moving member moves in a feedingdirection of the band-shaped metal plate and so as to disengage thefront end of the feeding pin and exit the same from the collaredthrough-hole when the moving member stops and moves in the reversedirection, and

the holding unit has a holding member, which contacts and holds theband-shaped metal plate so as to apply prescribed tension to theband-shaped metal plate when the moving member stops and which releasesthe band-shaped metal plate when the moving member starts to move in thefeeding direction of the band-shaped metal plate.

And, the heat exchange fin manufacturing machine of the presentinvention comprises:

a press unit for forming collared through-holes in a band-shaped metalplate and cutting the band-shaped metal plate to form heat exchange finshaving a prescribed length;

the tension device of the present invention; and

a suction unit for feeding the heat exchange fins to a stacking unit.

In the tension device, the holding unit may include:

a cam member making the holding member contact the band-shaped metalplate to hold the band-shaped metal plate and making the holding memberseparate from the band-shaped metal plate to release the band-shapedmetal plate; and

means for synchronously driving the cam member with operation of thepress unit. With this structure, the timings of holding and releasingthe band-shaped metal plate can be easily changed by changing the shapeof the cam member.

In the tension device, the moving member may synchronously move withoperation of the press unit, and

the driving means of the holding unit may be a servo motor. With thisstructure, the tension device can correspond to a high speed operationof the press unit.

In the tension device, the feeding unit may be provided on the exit sideof the press unit, and

the holding unit may be provided on the entrance side of the press unit.With this structure, prescribed tension can be easily applied to theband-shaped metal plate.

In the tension device, a fibrous member may be provided on a contactface of the holding member, which contacts the band-shaped metal plate.With this structure, damaging the surface of the band-shaped metalplate, which contacts the holding member, can be prevented.

In the tension device of the present invention, the holding unit, whichholds the band-shaped metal plate and applies the prescribed tensionthereto, is separated from the press unit. Therefore, the timings ofholding and releasing the band-shaped metal plate can be suitablyadjusted on the basis of the rotational speed of the press unit.

With this structure, deformation of the collared through-hole, which iscaused when releasing the band-shaped metal plate lags behind startingthe moving member to move in the feeding direction, can be prevented.

In case of changing rotational speed of the press unit, the timings ofholding and releasing the band-shaped metal plate can be easilyadjusted, so that the tension device can correspond to change of anoperation speed of the press unit.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described by way ofexamples and with reference to the accompanying drawings, in which:

FIG. 1 is an explanation view of an embodiment of a heat exchange finmanufacturing machine of the present invention;

FIG. 2A is a partial front sectional view of a holding unit provided onthe entrance side of a press unit shown in FIG. 1;

FIG. 2B is a side sectional view thereof;

FIGS. 3A and 3B are explanation views showing action of the holding unitshown in FIGS. 2A and 2B;

FIGS. 4A-4C are explanation views showing a relationship between theaction of the holding unit shown in FIGS. 2A and 2B and the action ofthe press unit;

FIGS. 5A and 5B are explanation views of another holding unit used inthe present invention;

FIG. 6 is a schematic view of the conventional heat exchange finmanufacturing machine;

FIG. 7 is a schematic view of the driving means used in the press unitshown in FIG. 6;

FIG. 8 is a schematic view of the moving member driven by the drivingmeans shown in FIG. 7; and

FIGS. 9A and 9B are explanation views of the feeding unit used in thepress unit shown in FIG. 6.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Preferred embodiments of the present invention will now be described indetail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a heat exchange fin manufacturing machineof the present invention. In the heat exchange fin manufacturingmachine, a band-shaped metal plate 10 is extended from a coil 12 and fedto a press unit 18 with adjusting tension, etc. applied to theband-shaped metal plate 10. In the press unit 18, a number of collaredthrough-holes are formed in the band-shaped metal plate 10 by a pair ofpress dies. Then, the band-shaped metal plate 10 is cut, by a cutter 26of the press unit 18, to form a plurality of elongated fin pieces havinga prescribed width. The elongated fin pieces are fed to a suction unit14 in order. When the elongated fin piece is fed a prescribed length tothe suction unit 14, a cutter of the press unit 18 cuts the elongatedfin piece to form a heat exchange fin having the prescribed length. Theheat exchange fin is sucked and held by the suction unit 14 and fed to astacking unit 28.

A hitch feeder 29, which is the feeding unit shown in FIGS. 7-9B, isprovided on the exit side of the press unit 18 shown in FIG. 1. Thehitch feeder 29 has been explained, so explanation will be omitted.

A holding unit 60, which holds the band-shaped metal plate 10 andapplies tension thereto when the movement of the moving member 50 of thehitch feeder 29 (see FIGS. 9A and 9B) in the feeding direction isstopped, is provided on the entrance side of the press unit 18.

In the holding unit 60, as shown in FIGS. 2A and 2B, cam members 68 areattached to side plates 64, which are vertically extended from a base 62on which the band-shaped metal plate 10 is moved, and a rotary shaft 66,whose one end is connected to a servo motor 72, and stationary members70 are spanned between the side plates 64. The servo motor 72 issynchronized with rotation of the press unit 18.

The cam members 68 respectively contact wheel members 82, which arerespectively and rotatably attached to shafts 80. Each of the shafts 80is spanned between vertical members 78, which are vertically provided ona holding member 76 capable of moving close to and away from the upperface of the base 62 on which the band-shaped metal plate 10 is moved. Acontact face of the holding member 76, which contacts the band-shapedmetal plate 10, is covered with a contact member 74 composed of afibrous material, e.g., felt. By covering the contact face of theholding member 76 with the fibrous contact member 74, the band-shapedmetal plate 10 can be securely held, and damaging the surface of theband-shaped metal plate 10 can be prevented.

As shown in FIG. 2B, springs 84, which bias the holding member 76 towardthe upper face of the base 62, are provided between the holding member76 and the stationary members 70.

In the holding unit 60, the rotary shaft 66 is rotated by the servomotor 72, which is synchronized with the rotation of the press unit 18,the holding member 76 connected to the wheel member 82 is lifted againstelasticity of the springs 84 when the cam member 68 attached to therotary shaft 66 reaches a position for upwardly moving the wheel member82 as shown in FIG. 3A, so that the band-shaped metal plate 10, whichhas been clamped between the contact member 74 and the surface of thebase 62, is released.

Further, the cam member 68 is moved from the state shown in FIG. 3A, inwhich the wheel member 82 is lifted, to the state shown 3B, in which thewheel member 82 is lowered. In this state, the holding member 76connected to the wheel member 82 is moved downward by the elasticity ofthe springs 84, and the band-shaped metal plate 10 is clamped betweenthe contact member 74 and the surface of the base 62.

Timings of holding and releasing the band-shaped metal plate 10 can beadjusted by changing the shapes of the cam members 68.

In the press unit 18 shown in FIG. 1, predetermined tension is appliedto the band-shaped metal plate 10 between the hitch feeder 29, which isprovided on the exit side, and the holding unit 60 shown in FIGS. 2-3B.

In FIG. 4A, the press unit 18 applies the tension. As shown in FIG. 4A,in the press unit 18, the band-shaped metal plate 10 is pressed while anangle of a crank shaft (crank angle) of the press unit 18 is 90-270°.When the crank angle is 180°, the dies of the press unit 18 are closed.While performing the press work, the band-shaped metal plate 10 isstopped. When the crank angle is 0° the dies of the press unit 18 areopened.

Preferably, the tension is applied to the band-shaped metal plate 10without applying a feeding load before stopping the feeding action so asto apply the prescribed tension to the band-shaped metal plate 10 at thetiming of stopping the band-shaped metal plate 10. Thus, as shown inFIG. 4A, the shape of the cam member 68 is formed such that the contactmember 74 starts to contact the band-shaped metal plate 10 at the crankangle of 330° after starting to feed the band-shaped metal plate 10, andthat the band-shaped metal plate 10 is securely clamped between thecontact member 74 and the surface of the base 62, as shown in FIG. 3B,at the timing of stopping the feeding action of the band-shaped metalplate 10.

In FIG. 4A, when the cam member 68 is further rotated until reaching thecrank angle of 130°, a clearance is formed between the contact member 74and the band-shaped metal plate 10 mounted on the base 62 as shown inFIG. 3A.

As shown in FIG. 4B, the contact member 74 may start to contact theband-shaped metal plate 10 when the crank angle is 300°, and theclearance may be formed between the contact member 74 and theband-shaped metal plate 10 mounted on the base 62 when the crank angleis 100°.

In case that a holding member, which contacts and holds the band-shapedmetal plate 10, is provided in the press dies of the press unit 18, thetiming of holding the band-shaped metal plate 10 with the holding memberand the timing of releasing the band-shaped metal plate 10 from theholding member cannot be independently adjusted from the rotation of thepress unit 18. In the press unit 18, when the band-shaped metal plate 10is released at the crank angle of 100° as shown in FIG. 4C, the timingof starting to hold the ban-shaped metal plate 10, at which theband-shaped metal plate 10 and the holding member are in contact witheach other, is the crank angle of 260° which is the symmetrical angle ofthe crank angle of 100°.

If the holding member contacts the band-shaped metal plate 10 beforefeeding the band-shaped metal plate 10 is started, an excessive loadwill be applied to the hitch feeder 29, which acts as the feeding unitfor feeding the band-shaped metal plate 10. Further, the front end ofthe feeding pin 52 is inserted into the collared through-hole 11, so thecollared through-hole 11 will be deformed by the feeding pin 52.

In the holding unit 60 shown in FIGS. 2A-3B, as shown in FIGS. 4A and4B, the holding member can start to contact the band-shaped metal plate10 after starting to feed the band-shaped metal plate 10, so thatapplying the excessive load to the hitch feeder 29 and the deformationof the collared through-hole 11 can be prevented.

When feeding the band-shaped metal plate 10 is stopped, the holding unit60 securely holds the band-shaped metal plate 10 and the prescribedtension can be applied to the band-shaped metal plate 10 at a positionbetween the holding unit 60 and the hitch feeder 29. Therefore,overfeeding or excessively feeding the band-shaped metal plate 10 can beprevented when feeding the band-shaped metal plate 10 is stopped, sothat bad products, which are formed by overfeeding the band-shaped metalplate 10, can be prevented.

In the holding unit 60 shown in FIGS. 2A-3B, the contact member 74 isbiased toward the band-shaped metal plate 10 by the springs 84, butanother holding unit 60 shown in FIGS. 5A and 5B may be employed.

In the holding unit 60 shown in FIGS. 5A and 5B, the holding member 74,in which the contact member 74 is attached to a bottom face, can be moveto and away from the band-shaped metal plate 10 mounted on the upperface of the base 62, which is biased by springs 86. An eccentric cam 88is rotatably provided between vertical members 78, which are verticallyextended from the holding member 76. By rotating the eccentric cam 88 bythe servo motor 72, the holding unit 60 can release the band-shapedmetal plate 10 (see FIG. 5A) and hold the same (see FIG. 5B).

The invention may be embodied in other specific forms without departingfrom the spirit of essential characteristics thereof. The presentembodiments are therefore to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription and all changes which come within the meaning and range ofequivalency of the claims are therefore intended to be embraced therein.

1. A tension device, comprising: a feeding unit for intermittentlyfeeding a band-shaped metal plate to a press unit so as to form collaredthrough-holes therein; and a holding unit for applying tension to a partof the band-shaped metal plate located between the feeding unit and theholding unit when the press unit stops feeding the band-shaped metalplate to the press unit, wherein the feeding unit is constituted by amoving member, which is capable of reciprocally moving in thelongitudinal direction of the band-shaped metal plate, and a feedingpin, whose front end is biased toward the band-shaped metal plate by abiasing member provided in the moving member, the front end of thefeeding pin has a slope face so as to insert the front end of thefeeding pin into the collared through-hole of the band-shaped metalplate and engage the same with an inner edge of the collaredthrough-hole when the moving member moves in a feeding direction of theband-shaped metal plate and so as to disengage the front end of thefeeding pin and exit the same from the collared through-hole when themoving member stops and moves in the reverse direction, and the holdingunit has a holding member, which contacts and holds the band-shapedmetal plate so as to apply prescribed tension to the band-shaped metalplate when the moving member stops and which releases the band-shapedmetal plate when the moving member starts to move in the feedingdirection of the band-shaped metal plate.
 2. The tension deviceaccording to claim 1, wherein the holding unit includes: a cam membermaking the holding member contact the band-shaped metal plate to holdthe band-shaped metal plate and making the holding member separate fromthe band-shaped metal plate to release the band-shaped metal plate; andmeans for synchronously driving the cam member with operation of thepress unit.
 3. The tension device according to claim 2, wherein themoving member synchronously moves with operation of the press unit, andthe driving means of the holding unit is a servo motor.
 4. The tensiondevice according to claim 1, wherein the feeding unit is provided on theexit side of the press unit, and the holding unit is provided on theentrance side of the press unit.
 5. The tension device according toclaim 1, wherein a fibrous member is provided on a contact face of theholding member, which contacts the band-shaped metal plate.
 6. A heatexchange fin manufacturing machine, comprising: a press unit for formingcollared through-holes in a band-shaped metal plate and cutting theband-shaped metal plate to form heat exchange fins having a prescribedlength; a tension device having a feeding unit for intermittentlyfeeding the band-shaped metal plate to the press unit and a holding unitfor applying tension to a part of the band-shaped metal plate locatedbetween the feeding unit and the holding unit when the press unit stopsfeeding the band-shaped metal plate to the press unit; and a suctionunit for feeding the heat exchange fins to a stacking unit, wherein thefeeding unit is constituted by a moving member, which is capable ofreciprocally moving in the longitudinal direction of the band-shapedmetal plate, and a feeding pin, whose front end is biased toward theband-shaped metal plate by a biasing member provided in the movingmember, the front end of the feeding pin has a slope face so as toinsert the front end of the feeding pin into the collared through-holeof the band-shaped metal plate and engage the same with an inner edge ofthe collared through-hole when the moving member moves in a feedingdirection of the band-shaped metal plate and so as to disengage thefront end of the feeding pin and exit the same from the collaredthrough-hole when the moving member stops and moves in the reversedirection, and the holding unit has a holding member, which contacts andholds the band-shaped metal plate so as to apply prescribed tension tothe band-shaped metal plate when the moving member stops and whichreleases the band-shaped metal plate when the moving member starts tomove in the feeding direction of the band-shaped metal plate.